


Do As I Say

by KrisWitherKay



Category: RWBY
Genre: Asphyxiation, Come Inflation, Dildos, F/F, Face-Fucking, Futanari, Master/Slave, My First Smut, Shameless Smut, Sibling Incest, Unconscious Sex, What Have I Done
Language: English
Status: Completed
Published: 2016-08-05
Updated: 2016-08-05
Packaged: 2018-07-29 13:09:33
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 4,191
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/7685791
Author URL: https://archiveofourown.org/users/KrisWitherKay/pseuds/KrisWitherKay
Summary: <blockquote class="userstuff">
              <p>When Ruby gets bored with Yang's lacklustre performance she decides to take the reins herself. Immediate warnings for shameless incest smut.</p>
            </blockquote>





	Do As I Say

Ruby considered herself to be a fairly simple minded person. She didn’t think about the greater problems of the world like poverty, war or racism a lot. She didn’t really know if her words would make a difference to those causes in the grand scheme of things so she was most likely better off not thinking about those things and then she wouldn’t get frustrated when her voice alone didn’t reach everyone in the world.

Instead, Ruby allowed herself to be pleased by less complicated things like the enticingly bright colours of fresh, ripe, home-grown strawberries that had just been washed of all their outdoor grime or the thick, sweet aroma of chocolate chip cookies that bathes her senses like the fierce but comforting heat of the oven as it’s flung open. More recently she had discovered the satisfaction of running a whet stone down the smooth curve of Crescent Rose just to be rewarded with that beautiful sound from the blade that made her scalp tingle and her mouth water.

Yet now, as she lay back naked on her sister’s bed with her penis standing to attention, her legs spread wide and said sister down between them showering her balls and her lips with kiss after kiss after kiss she could confidently say that she wasn’t very pleased by it.

It was true that if Yang kept up this action over an extended amount of time, possibly turning up the heat so far through that Ruby would no doubt finish and she knew this through experience. Ever since they had started this daring, sexual, incestuous relationship between them they had tried quite a few things and came close to a lot of lines that shouldn’t be crossed. As they were right now, they could probably go back to the way they were before with minimal repercussions, blowing it off as a phase where they were “ _finding themselves_ ”. But the two grew closer and closer every time they made love to reaching a point of no return. Ruby didn’t know what would happen to them after they crossed that line but she didn’t really care, she was a simple minded girl after all.

But just this once, Ruby wanted to know what it was like on the other side. She wanted this to be their best time together, she wanted every time to be their new “best time together” but at the rate this was going it was going to end up the same as it always does whenever Yang gives her head. Ruby would empty her balls, some of it would go on Yang and she would love it just like she always has, some of it would go on Ruby herself and Yang would more than happily lick it off her but the majority of her load would just make a mess on the bed and that would be the end of that. Ruby needed _more_ which meant this little display had to stop.

“Yang.” Ruby called to her and Yang answered with a hum that pulsed straight through the testicle that Yang had in her mouth. It was the most stimulating thing she’d done this entire time. But Ruby would change that. “I want to try something new.”

“Yeah?” Yang disappointingly let go of her balls and tried to go back to kissing her groin but Ruby pushed her away.

“What we’ve been doing all this time has been pretty tame.” Ruby admitted as she climbed down from Yang’s bunk and as soon as Yang saw her little sister’s cock twitch in anticipation her own dick became even harder with renewed vigour and she climbed down after her. “But I want to turn things up a notch this time.”

“What did you have in mind?” Yang tried to be sultry as she stroked Ruby’s bare backside as the younger sister rummaged around in their team’s cupboard but Ruby wasn’t fooled. That effortlessly sexy girl that everyone knew and would kill to be with was someone Ruby didn’t see. Ruby knew how snotty her face got when she cried during Titanic when Jack died. She knew that she had habitually picked her nose for years and she still did it here at Beacon when she thought no one was looking but she also knew how shamefully wet her pussy got when Ruby was on top. Ruby found the shoe box in the back on the cupboard and when she pulled it out she lead her sister to the middle of the room and opened the box.

“I’m going to tell you the truth. It might not be what you want to hear right now but I can promise that everything will go up from there.” Ruby gestured for Yang to stay where she was and that was when she pulled the first dildo from the box. Ruby heard Yang gasp a little at its size and she struggled to supress her smile. Of course she was surprised, she had never shown Yang her recent purchase so Yang was free to marvel at the huge, pitch black dildo in her hands. Ruby turned it over a few times so Yang could really know what she was in for but when Ruby brought out the cable and the pump that was attached to it she really wasn’t so sure that she knew anything anymore. “Yang, you are absolutely terrible at sucking dick. For someone with tits that big and a mouth as smart as yours you really don’t know how to use them.”

Yang wasn’t sure if she was hearing this right. Her own sister was saying that her technique that she had been using for so long now was that bad and actually had to stop her to take the reins. She should be appalled, she should be completely turned off. But hearing that new, peremptory, domineering tone from her usually immature sister and to see her handle such a huge dildo like she knew the girth and every single deep groove and vein like the back of her own hand made Yang’s already swollen lips and meat pulse with a deep, primordial lust that she had never known. She didn’t answer Ruby’s accusations, she couldn’t. Yet if she wasn’t left speechless already, when Ruby pulled out the second dildo with the same kind of cable connected to it Yang’s brain melted in to a puddle just like the one she was sure her loose, wet lips were making on the laminate floor.

“So I’m going to teach you exactly what you’re good for.”

Ruby watched amusedly as her big sister’s dick twitched at her forceful words. Yang took this is a cue to touch herself and she was allowed to jerk her meat over her jailbait, little sister while she set her toys up on the floor. Yang saw now that the dildos, as well as having cables and pumps coming from them also had suction cups on the bottom. Ruby secured them right next to each other on the laminate floor and made sure that they were stuck fast. Yang stayed where she was but she knew exactly what was coming.

“Make yourself at home.” Ruby told her and Yang wasted no time kneeling over the huge, fake cocks. As soon as the front dildo poked at the entrance of her drenched pussy, Yang began to quiver. She wasn’t even sure that she could call this foreplay but it was the best that she had ever had and they had barely even started. The sweet, sweet ache in Yang’s cunt told her that this time it was going to be different. The hot, hard breaths from behind her lips knew it was going to change her as a person and the thick, musty smell of pheromones from her own skin told her that she couldn’t have been any more ready to be broken and reformed by her sister. Yang lowered herself a little more on to both dildos, hiding the heads away inside herself and continued down until she thought she couldn’t take any more.

“What’s the matter, Yang? Don’t tell me you can’t go any lower?” Yang looked up at her sister and was surprised to see her big cock reaching out and over her face, leaving it resting on her cheek where she could take in every last bit of that delicious aroma and cloud up her mind even further with only thoughts of Ruby’s hanging member. “I know you can do better than this Yang, those dildos are shorter than me but I know that you can take me balls deep. What’s up with that? Come on, open up that slutty, cock sleeve for me, big sis.”

Yang’s dick was plunged in to another series of energetic twitches at Ruby’s derogatory comments hit home. She really must have been an unbelievable slut to be doing all of this so readily. Every word, every breath and every heartbeat was bringing her closer to fall under Ruby’s filthy spell. But Yang realised as Ruby knelt down and straddled her thighs that she was already under Ruby’s spell and had been since the beginning and as Ruby pushed down emphatically on her hips and her dripping cunt and spread arsehole were filled to such an unfamiliar level like she had never taken a dick before in her life she felt the familiar fires of her ultimate high begin to stir her up and sap her of her strength and it was only progressed as Ruby took both of their firmly erect shafts in one of her hands and pumped them at her own leisurely pace, teasing the heads and foreskin with her free hand.

Yang could feel her chest threatening to burst as her heart rate shot through the roof and she could feel her heart thundering through her breasts, pushing her shy nipples out until they were fully erect. Her walls were trembling, trying their best to milk the fat dildo reaching right up to her cervix but it was no use, Ruby had full control of both of the reservoirs lodged inside her and she could let them loose at any time and as Yang felt her foreskin peel back as her cock swelled in Ruby’s hand and she began to pump faster she really hoped that she would let them go just as she was about to.

Though it wasn’t to be, Ruby went nowhere near the pumps as her elder sister was taken over by the sweet rolls of an orgasm and the fresh ropes of hot cum from her engorged cock began to fly. But Yang didn’t have much time to revel in the bliss and Ruby quickly but firmly gripped her head and bent her down, thrusting Yang’s own dick far in to her mouth and held her there as she unloaded her fertile load in to herself.

“Swallow it all, Yang.” Ruby’s voice was in her ear. “Don’t miss a drop. You need this cum down your throat.”

Yang’s eyes rolled back as her orgasm intensified and so did the ropes she was shooting over her own tongue. She’d never tasted her own cum before but as she swallowed everything she had to give she had to say that the taste wasn’t all that bad. It was clearly sweet, she didn’t know what the sugar content was like in semen but it was enough to make her brain melt and her breath hitch, Yang noticed as more ropes poured in that it was noticeably saltier than what she remembered Ruby’s being, one particular rope made a direct hit with the back of her throat and as she coughed, still impaled on her own cock, the load came straight back out of her nose and coated her balls.

Ruby used that cue to untangle her sister and push her down one last time on to the dildos now that she was nothing but a puddle and just as Ruby had predicted, Yang’s coccyx hit the floor, a new bulge was visible in her abdomen and Yang cried out.

“Ah, mommy!”

Ruby had to say that she was a little taken aback at that. Of all things to call her, she would have thought that she might pick one that doesn’t hit so close to home, they both had their own mommy issues but when Ruby thought about how she had absolutely destroyed any chances of ever having a normal relationship between them again she thought it might be easier for them if they thought up new names for each other. Though Ruby would leave it for a later date, there were more pressing matters at hand, like her raging erection.

“You want to call me ‘mommy’, baby?” Ruby asked though she didn’t expect an answer. “You want to suck mommy’s big futa dick?”

Yang looked up at her as a changed woman; Ruby’s own personal slut. Her eyes were half lidded, her breath was ragged and she hung her mouth open, showing Ruby the good work she did as she swirled a mouthful of cum around in her mouth and gargled it.

“Ah wamma, mommy.” Yang tried her best to show her eagerness and keep the cum in her mouth at the same time.

“That’s a good girl.” Ruby praised her as she stroked her hair and brought the blonde forwards so she could suck the tip of her dick, which she readily did, immediately getting under Ruby’s foreskin with her tongue and pushing it back so Ruby could stretch to her full length without worry of hurting herself. This let Yang get to her favourite place of Ruby’s dick, the hard ridge at the base of her head, Ruby understood this part as the corona after she had gotten curious one day and researched her own anatomy. Yang loved to tease her sister as she moved her lips over this ridge, to watch the expression on her face and to coax her in to taking charge. “Now Yang, I need you to follow everything I say, exactly as I say OK?”

Yang continued to suck her dick but managed a nod as Ruby’s dick pushed her cheek out.

“Good, now put your hands on me, anywhere but my dick.”

Yang did as she was told. She slid her hands around her sister’s strong thighs and took a gentle hold of her bum cheeks. She was comfortable like that, it was like a little hug and Ruby seemed to like it too as she gently pushed forwards as she twitched a little between Yang’s lips.

“I don’t think this will take long at all as long as you do as mommy says.” Ruby told her and she took a hold of her head again, lacing her fingers in Yang’s thick, wavy hair. “All you have to do is let me have my way and not let go.”

Ruby was thrusting in to Yang’s mouth by now, not too hard and not too deep. Yang kept herself relaxed so Ruby could move her how she wanted and as she met her sister’s eyes she saw that expression again on her face that really showed her how much she loved her. But the thrusts were getting deeper, it was hard for Yang to keep her concentration and hold her form but Ruby was just getting started.

The very next thrust was an irregular one that instantly made her recoil. Ruby slammed her abdomen right up to Yang’s face, burying her nose in her pubic hair and cut off her air supply, effectively sheathing her hard, fat cock in Yang’s throat. Yang hadn’t been expecting it at all, even though she had very little in the way of a gag reflex, she had been in the middle of a breath when Ruby had done it and she wretched violently and pulled away.

“Hey now, what have I been telling you this whole time?” Ruby cooed at her. “Mommy’s gonna teach her little slut exactly what she’s good for.”

Yang would have spoken up had it been any other circumstances but the taste of dick was hitting her hard and her thoughts were jumbled from the shock. She had no strength to fight back, not that she really wanted to in the first place and Ruby took full advantage of the fact. This time Ruby gathered the hair at the back of Yang’s head in her hand and held it securely in a ponytail, her other hand took a hold of Yang’s jaw and moved her forwards on to her dick once again. Ruby tightened her grip stinging Yang’s scalp but only for a moment. It was meant as a warning.

_Mommy’s going to throatfuck you now so be a good girl and do as I say._

And she did. Yang put her hands back on Ruby’s thighs this time and let herself relax and fall to her inner slut as her sister pounded the back of her mouth bringing forth some indecent noises and a load of saliva and mucus every time she pulled back and Yang attempted to breathe. Ruby used everything that Yang gave her to her advantage. When she thought that Yang was getting too vocal she would plunge her sister’s throat on to her cock and use her mucus lined oesophagus as a sex toy until Yang could feel her sister’s cock swell in her throat with an approaching orgasm and the tears that had been brimming in her eyes finally fell and smudged her makeup. Yang was taken by surprise again when Ruby once again submerged her dick in the depths of Yang’s throat, forcing her to take in the overwhelming stench of Ruby’s pheromones from her thick carpet of pubes. But this time Ruby held her there, grinding and thrusting at different parts of Yang’s face, twisting her dick at different angles as she pushed, but the fat dildos in Yang’s pussy and arsehole kept her from moving around.

“You’ve got such a nice throat, Yang.” Ruby cooed as she met Yang’s crossed eyes and gently stroked Yang’s neck where she knew her cock reached to. “Mommy’s so proud of you, darling.”

Yang felt the deep warmth of pride rise in her chest as her vision swam from a lack of air and her second orgasm approached fast.

“But this has to end. Mommy’s so close to emptying her big, juicy balls and filling you to the brim it almost hurts. Are you ready, my little slut?”

Yang physically didn’t have the energy to express how much she wanted – how much she _needed_ \- a stomach full of Ruby’s potent sperm but both girls had been edging closer to an orgasm the whole time and they were both due for the most satisfying release and Yang was determined to give her it. Ruby didn’t wait for an answer either as she slid her cock out of Yang’s throat until just the tip was choking her and both girls felt something turn inside Ruby a split second before she went on a rampage and ravaged Yang for everything she was worth.

Ruby pumped her cock through Yang’s throat like it was their last time together. Yang didn’t know how long she had gone without air but it had to be approaching a minute now and she was well and truly feeling the effects. She could feel somewhere in the back of her mind as her eyes rolled back slightly that it wasn’t right and that her body was convulsing as it forcefully tried to take in the thick, musty air that it desperately needed but Yang was in love with the feeling and Ruby was utterly in charge.

“You know darling,” Ruby started through laboured breaths as she continued to pummel Yang’s whorish face. “I’ve spent the last few days cumming as much as I can in secret; filling the _huge_ reservoirs in those dildos until they’re fit to burst and I can’t wait until I let them both loose inside you. I don’t know how long a sperm cell can last outside of my balls but there should be one or two cells still alive. I wonder if my babygirl will get pregnant from mommy’s seed? _I sure hope so~_ ”

Yang could feel thanks to Ruby’s big, pulsing cock that the dirty talk was having an effect on the both of them and they were both on the brink of their climaxes but whereas Yang didn’t even know if she would be conscious to let off her one orgasm, Ruby would be in full control when she let off all three and filled her to the brim and after what she had vaguely heard her sister say, as Yang felt her oxygen deprived arms fall to her sides, she sure hoped that she would get pregnant too.

And as if on cue, the flood gates were opened. Ruby squealed in delight as she skewered her elder sister on her cock for the final time and stamped on both the pumps for the dildo reservoirs as hard as she could in the throes of her biggest orgasm to date and the three biggest dicks Yang had ever taken in her life erupted explosively in every one of her fuck holes.

Ruby watched as the old semen from the dildos was expelled inside of her sister and her stomach bulge was pushed out just a little more every time she stamped on the pumps after that until the big, black cocks had completely emptied inside her backside and in her fertile womb just like Ruby herself was doing down Yang’s slimy throat. Ruby had taken a little break from cumming after she had filled both the dildos to replenish her own supply of spunk and she could say with pride now as her balls quivered through her orgasm that she was letting go of one of her biggest and thickest loads, whether Yang was still conscious or not she didn’t know. Her empty eyes were still staring in to her own and as soon as she had felt Ruby’s cock twitch inside of her tight throat she had let her own second load go from her big dick, firing it with vigour between Ruby’s ankles and across the floor where more and more settled after every spasm and every rope from Yang’s dick until she had indeed made her last hurrah.

Ruby didn’t try to catch Yang as her strength left her and she slumped down, truly unconscious on to the floor. The dildos slopped out of her limply and her gaping arsehole and quivering cervix let out all the old cum that they couldn’t hold, spill out to gather and pool beneath her sister. Ruby managed to hold back another few strong ropes as her cock slid out of Yang’s throat when she fell and her unconscious body finally took a well-deserved breath and Ruby took the opportunity or a new position to spread Yang’s legs and let out the rest of her impossibly large and potent nut balls deep inside of her sister’s cunt, which her overflowing womb readily made room for and welcomed with open arms.

Ruby made sure that Yang wasn’t in any danger of choking if she happened to be sick in her sleep after her orgasm had finished and she felt her tense muscles relax and her domineering phase subside for now. Ruby draped a large towel over Yang where she thought it wouldn’t get soaked by either of their pools of cum and slipped a pillow under her head. She realised that Yang would probably be out of it for a while as she cleaned herself up and got redressed so they had really struck it lucky that their partners were out on a couple of solo missions over the weekend and they were free to do this kind of thing.

Before Ruby headed out of the door to head to lunch, she considered cleaning Yang up as well but it would be a good cooldown exercise for her while she got to grips with her new situation. Ruby licked up some of her own cum that lay on Yang’s lips and left her with a passionate kiss and a note that she laid on her pillow for when she woke up.

“Be back soon, Yang.” Ruby called as she left even though her sister couldn’t hear her anymore. “I love you.”  
Yang woke up a couple of hours later feeling cold, wet and sticky but very, _very_ satisfied. She saw the note Ruby had left on the pillow and read it before she got to cleaning up their mess.

“ _To Yang,_  
_You were absolutely astounding this morning and I’m so proud of you for taking me as well as you did, darling!_  
_As a reward, I’ll let you have me however you want tonight, god only knows my babygirl deserves it after everything I put you through._  
_I love you so much, see you soon!_  
_Love from Mommy <3_ ”

“Aww, Ruby.” Yang mumbled to herself as she hugged her pillow. “I love you too.”

**Author's Note:**

> So Monday the 25th of July was my fic blog's 3rd birthday. Because I usually upload all my stuff on FF I had to create this account specifically for this work because FF doesn't allow lewds of this level. The signing up process was a little strange to me but I'm liking the extensiveness of the additional tags, I might even have to write more smut specifically to use some of these golden tags hahaha
> 
> But anyway I hope someone out there enjoys this kind of thing. It's my first time trying to write explicit scenes so I wouldn't mind critiques if someone who is well versed in writing this kind of thing happens to see this, but I hope you'll go easy on me.
> 
> If you've got this far, I'll presume you powered through the whole thing so I'd like to congratulate and thank you. If you'd like to find my other SFW stuff I go by the same username on FF.


End file.
